Initiating a call in a communications system

ABSTRACT

A method for initiating a call in a communications system comprising a mobile communications device connected in a mobile communications network. The mobile communications device is allocated a mobile identifier for a first, mobile communications service provided by a mobile communications service provider and is allocated a second identifier for a second communications service provided by a second communications service provider that is different from the first, mobile communications service. The method comprises receiving over a data connection, at a switch, a request from the mobile communications device, comprising the second identifier, to initiate a call using the second communications service and adding, at the switch, the mobile identifier to the request and forwarding via a further network, the request comprising both the second identifier and the mobile identifier.

RELATED APPLICATIONS

The present application is a National Phase entry of PCT Application No.PCT/GB2014/000052, filed Feb. 14, 2014, which claims priority to EP13250036.4, filed Mar. 26, 2013, the contents of which are incorporatedherein by reference in their entireties.

TECHNICAL FIELD

Embodiments relate to initiating calls in a communications system.

BACKGROUND

US2011065426 describes a method of displaying caller ID in a WiMAX/GSMintegrated support portable terminal In particular, US2011065426describes initiating a VoIP call in a mobile network. WO2008027065describes initiating a VoIP call in a mobile network in which atemporary directory number is associated with the VoIP destinationdevice.

SUMMARY

A method for initiating a call in a communications system comprising amobile communications device connected in a mobile communicationsnetwork. The mobile communications device is allocated an identifier fora mobile communications service provided by a mobile communicationsservice provider and is allocated an identifier for a secondcommunications service provided by a second communications serviceprovider that is different from the mobile communications service. Themethod comprises receiving, at a switch (e.g. a softswitch operating ona hardware server), from the mobile communications device, a request,comprising the second identifier, to initiate a call. The methodcomprises adding the mobile identifier to the received request at theswitch and forwarding to a communications service provider the requestcomprising both the second identifier and the mobile identifier.

Use of the SIP/VoIP service may be linked to another account for billingpurposes, e.g. so that call charges are not accrued to a mobilecommunications billing account. Advantageously, high-rate mobile callcharges may be avoided by use of the data connection to make calls andby billing these to a non-mobile account. A method is provided forassociating charges incurred using the second communications service(e.g. SIP/VoIP) with a billing account for a different, thirdcommunications service. The mobile communications device is associatedwith a mobile communications service billing account. A charge relatingto the call using the second, SIP/VoIP communications service isallocated to a billing account for the third communications service.Charges for SIP/VoIP calls from the mobile phone may then be charged toa telephone account associated with a different communications deviceand a different communications service, e.g. the user's home phone line.

Where the second identifier may not allow calls to be routed back to theuser's mobile device (e.g. where it is a non-geographic number),inclusion in the request, of the user's mobile identifier advantageouslyenables the recipient of the call to use the mobile number to contactthe user and, possibly, to also identify the caller.

The mobile communications device may be operable in both a mobiletelephony network and a data (IP) network. A SIP/VoIP call over the datanetwork from the mobile phone is associated with a SIP ID and,additionally, is tagged at a softswitch or other server handling theSIP/VoIP call with the phone's mobile number, e.g. in the form of apresentation number. When the softswitch forwards the call (e.g. to thePSTN), a phone receiving the SIP/VoIP-originated call is able toidentify the calling party's mobile number and is able, as a result, tocontact the calling party by using the calling party's mobile number. Inorder to facilitate handling by the softswitch of the mobile phone's SIPID, this may be set to an unallocated non-geographic telephone number.

To enable the mobile device to operate according embodiments to theinvention, the user may download an app from a suitable app website. Theapp initiates a VoIP account set up process with a communicationsprovider.

A billing arrangement may be set up by receiving, from a mobilecommunications device, a request to set up, with a third communicationsservice provider, a billing account for the second communicationsservice. Allocating an identifier to the billing account with the thirdcommunications service provider and associating the identifier with themobile communications device.

A switch comprises: first and second communications interfaces. Thefirst communications interface is for communicating over a dataconnection with a mobile communications device connected in a mobilecommunications network. The mobile communications device is allocated anidentifier for a mobile communications service provided by a mobilecommunications service provider and a second identifier for a secondcommunications service. The second communications interface is forcommunicating with a further communications network. The switch alsocomprises a processor configured to control operation of the switch. Theprocessor controls operation of the switch to receive via the firstcommunications interface, a request from the mobile communicationsdevice to initiate a call using the second communications service; inwhich the received request comprises the second identifier. Theprocessor also controls operation of the switch to add the mobileidentifier to the received request and forward, via the secondcommunications interface to the further communications network, therequest comprising both the second identifier and the mobile identifier.

A communications system comprising the above switch.

BRIEF DESCRIPTION OF THE DRAWINGS

In order to aid understanding, embodiments will now be described by wayof example with reference to the drawings in which:

FIG. 1 shows in schematic form a system for implementing an embodiment.

FIGS. 2 a-2 n show screens suitable for display on a mobile deviceoperating according to an embodiment.

FIGS. 3 a and 3 b show a signal flow diagram according to an embodiment.

FIGS. 4 and 5 show logic flow diagrams according to embodiments.

DETAILED DESCRIPTION

Some embodiments cover aspects of the SmartTalk service offered byBritish Telecommunications plc of 81 Newgate Street, London EC1A 7AJ,United Kingdom (BT), although embodiments are not limited thereto,SmartTalk is aimed at users of a communications service provided to amobile device and allows linkage of a customer's mobile phone with theirhome phone calling plan.

According to an embodiment, the system may allocate to a mobilecommunications device, a non-geographic telephone number (e.g. 03number) as unique identifier (UI) for a second communications service(for example, one based on session initiation protocol SIP) accessiblefrom the mobile device. The UI is dedicated to the user of the mobiledevice and, where an app is provided on the mobile device to manage thesecond communications service, the UI for the second communicationsservice (e.g. a non-geographic number) is allocated to the app runningon the mobile device. There is no requirement for the UI to also beassociated with the mobile communications service that is also accessedfrom the mobile device. Where the app manages the second communicationsservice from the mobile device, conventional software may be provided onthe mobile device to manage the mobile communications service.

Whereas a mobile communications service, e.g. a mobile telephonyservice, is normally linked to an account with a provider of the mobilecommunications service (e.g. to provide for billing for use of themobile communications service), embodiments enable a user toadditionally link with a third account (i.e. through a serviceidentifier) a second communications service accessed directly from theirmobile device. The third account (referred to herein as the “home”account) is an account with a provider of a third communicationsservice. The UI for the second communications service is then associatedwith the third service. For example, to accept charges for use of aSIP/VoIP communications service, the UI for the SIP/VoIP communicationsservice may be associated with a home phone line account.

The third communications service may be provided by a different serviceprovider to the service providers for the mobile and secondcommunications services. The third communications service may beassociated with a home telephony service, for example, a landlinetelephone service supplied to the user's residence but may, according toa further embodiment, be associated with a provider of another kind ofcommunications service. The home telephony service may be registered tothe mobile communications service user (hereafter “mobile user”) or toanother person but where the mobile user has access to the hometelephony service. For example, the home telephony service may beassigned to a first family member where the mobile user is anothermember of the same family, sharing the same residence to which the hometelephony service is provided.

FIG. 1 shows in schematic form, a system for implementing an embodiment.In the system of FIG. 1, a user (not shown), i.e. a consumer oftelephone services, operates mobile communications device 100, which maybe a smart phone, tablet, laptop computer or other network-enabledmobile device. The user may operate mobile communications device 100 tocommunicate via mobile telephone network 112 with telephony terminaldevices via one or more communications service provider network. Theuser may also operate mobile communications device 100 to communicateover a data connection via Internet 104 with web servers, such asapplication provider website 102, integrated voice response (IVR)platform 108 and Softswitch 122. The data connection may be set up overWi-Fi or a mobile data connection. Mobile communications device 100 isallocated an identifier (the “mobile identifier”), e.g. a mobiletelephone number, for a mobile communications service provided by amobile communications service provider.

As part of a process of registering for a new communications service orconfiguration of an existing communications service, the user may alsooperate mobile communications device 100 to communicate over Internet104 with servers operated by a communications service provider, such asAPI Layer application 106, operated by British Telecommunications plc.Mobile communications device 100 is also allocated an identifier (the“second identifier”) for a second communications service, e.g. a. UI fora SIP/VoIP communications service provided by a second communicationsservice provider that is different from the mobile communicationsservice. As indicated, above, this second identifier may, according toan embodiment, be a non-geographic number.

API Layer application 106 provides an interface for the user to theinternal systems operated by the communications service provider. Asshown in FIG. 1, these internal systems comprise customer order softwarefunction (MCSO) 114, customer database server 116, phone numberrepository (MNUM) 118, switch manger 120 and billing platform 126.

In order to provide the service in a secure manner, a user may berequired to register with the service provider. To initiateregistration, the user may download from a suitable application providerwebsite 102 to their mobile device 100 an application (or app)supporting an embodiment. Suitable application provider websites willinclude the Apple iTunes® store and the Android™ Marketplace/Google®Play website. Once downloaded, the user launches the app on mobiledevice 100, which sets up a connection (such as TCP/IP) via Internet 104with API Layer application 106. The app guides the user through aregistration journey (described below—see screens-shots FIGS. 2 a to 2 nand signal flow diagrams FIGS. 3 a, 3 b). The registration journeycomprises an exchange of information between the app and the API Layerapplication 106, which runs on a server-based hardware platform (notshown).

According to an embodiment, PSTN or other call charges in relation tothe outgoing SIP/VoIP call may be billed to the user's home account. Alogic flow according to an embodiment is shown at FIG. 5. At 510,billing platform 126 is configured to map the non-geographic number tothe user's home telephony account. At 520, a SIP/VoIP call request isreceived at softswitch 122 and, in response at 530, a call record isgenerated by softswitch 122 referenced to the second identifier (i.e.softswitch 122 treats the non-geographic number as a call ID). At 540,the call record is sent to billing platform 126. At 550, call chargesare then billed by billing platform 126 to user's home telephonyaccount. This billing transfer mechanism makes no use of thepresentation number (i.e. the mobile phone number), except that thepresentation number may be shown on the bill to aid clarity.

The mobile user may already be registered with the home telephonyservice provider, for example, by virtue of a BT OneID account. Ifalready registered, the user may extend the existing registration to thenew service provided through the app by entering credentials (usernameand password) associated with the existing registration. The existingregistration may, according to an embodiment, provide the user withcontrolled access to an existing service provided by the serviceprovider (e.g. a home telephony service), however, this is notnecessarily the case and, according to a further embodiment, theexisting registration is not related to a current service. If the userdoes not have a suitable existing registration, they can request sign-up(i.e. so as to create a new account) in a manner that is described next.

In the course of the registration journey, the app displays, to theuser, a sequence of screens: as shown in FIGS. 2 a to 2 n. FIG. 2 a showa welcome screen 200 for display on mobile device 100 at the start ofthe registration process. Welcome screen 200 comprises twouser-selectable fields “I am not at home” 202 and “I am at home” 204which, at the same time, prompt the user for input and provide a meansfor receiving input from the user. The user-selectable fields may bemade to resemble buttons on which prompt text is displayed and where themobile device is configured to detect selection of a user-selectablefield either by the user touching the display in the region of thebutton (for touch-sensitive displays) or selecting the button with apointing device (such as joystick or mouse) and operating an inputcontrol, such as a switch.

When mobile device 100 detects input from the user, it determines asubsequent step based on the input received as interpreted by operatingand application software loaded on the device. When the user selects “Iam not at home” 202, mobile device 100 may display an error screen (notshown) reminding the user that registration requires the user to haveaccess to their home phone (for reasons that will become evident,later). When the user selects “I am at home” 204, mobile device 100 maydisplay screen 210 to prompt the user, as shown in FIG. 2 b, to indicatewhether or not they have an existing billing account with a telephonyservice provider (for example BT) for their home telephony service. Theprompt may take the form of two user-selectable fields, 212, 214,similar to those described above, with reference to FIG. 2 a butdisplaying respective prompt text asking the user to login to anexisting account (212) or to register (create a login) with thetelephony service provider (214).

When the user selects “login” user-selectable field 212 on screen 210,mobile device 100 displays login screen 220 shown in FIG. 2 c,requesting user login credentials. On login screen 220, the user isasked to input their user name and password associated with an existingbilling account with the provider of their home telephony service.

In the alternative, when the user selects “create a login”user-selectable field 214 on screen 210, mobile device 100 displaysscreen 230 shown in FIGS. 2 d and 2 e, requesting user to register tocreate a login. FIGS. 2 d and 2 e represent a single, extended screendisplay 230, shown split into two parts in the drawings so as better tofit the page, whereas, when displayed on mobile device 100, this wouldappear as a single screen, albeit, one that may require the user toscroll down in order to view the whole content. FIGS. 2 d and 2 e show aseries of empty fields, e.g. 232, 234, 236 with prompts for the user toenter information to support a request for a username and passwordassociated with their home telephony service. Information to support therequest may comprise personal details to enable the user to beidentified.

On successfully logging in (or successfully creating a new loginregistration followed by a successful login) mobile device 100 displaysscreen 240 shown in FIG. 2 f comprising text 242 to inform the user thatlogin has been successful.

Where the user has requested to extend an existing registration (e.g.with the home telephony service provider), API Layer application 106checks, with the existing service provider, the user's credentialsprovided as part of the sign-up process. If accepted, API Layerapplication 106 may prompt user via the app for an identifier of thehome telephony account which is to be linked to their mobilecommunications service, e.g. a phone number associated with the hometelephony service. FIG. 2 g shows screen 250 comprising text 252 toprompt the use to enter, using on-screen keyboard 254, their home phonenumber. API Layer application 106 checks that the number entered by theuser is (or relates to) a valid phone number (i.e. that there is asuitable account associated with the number). Alternatively, API Layerapplication 106 may compare the identifier with account details obtaineddirectly from the home telephony service provider.

According to an embodiment, the mobile number and home telephony accountnumber are checked to ensure that the user has access rights to both. Ifthe number entered by the user on screen 250 is found to be valid, theequivalent home phone number may be called by API Layer application 106via IVR platform 108. API Layer application 106 may provide a code(PIN1) via SMS (i.e. using telephony signaling over the mobile telephoneconnection supported by GSM network 112) to user's mobile device 100together with appropriate instructions. FIG. 2 k shows screen 270 withtext 272 prompting the user to enter using on-screen keyboard 274, thePIN1 code provided over the user's mobile phone connection. When theuser follows the instructions and enters the PIN1 code via the app, theapp sends to API Layer application 106 (i.e. over a mobile telephoneconnection, supported by GSM network 112), the code entered by the user.API Layer application 106 checks the received code value against PIN1code provided to mobile device 100—if the code received from the appmatches PIN1 code provided to mobile device 100, API Layer application106 verifies user's mobile phone number.

API Layer application 106 may provide a second code (PIN2) to the userin the course of the call (for example, by means of a computer-generatedvoice message) and prompts the user to enter the PIN2 code via the appon their mobile device 100. FIG. 2 h shows screen 260 with text 262prompting the user to enter, using on-screen keyboard 264, the PIN2 codeprovided over the user's home phone line. The app sends the code enteredby the user to API Layer application 106 as a text (SMS) message. Thetext message is sent over a mobile telephone data connection, supportedby mobile telephone network 112, such as a GSM network. API Layerapplication 106 checks the code received from mobile device 100, againstthe PIN2 code provided in the course of the call to home phone 110—ifthe code received from the app matches the PIN2 code provided to thehome phone number, API Layer application 106 verifies user's home phonenumber.

Having verified an identity for both the user's home phone 110 andmobile device 100, API Layer application 106 now initiates a back-endprocess to set up the account, while displaying further screen 280, asshown in FIG. 2 m, confirming to the user that the system is now readyto associate their mobile device with their home telephony servicebilling account.

In order to initiate the back-end process to set up the account, APILayer application 106 hands control to customer order software function(MCSO 114). MCSO 114 serves as an aggregation and orchestration functionfor placing orders. MCSO 114 starts to build, on customer databaseserver 116, a user profile for VoIP service for mobile device 100.

MCSO 114 makes a software call to phone number repository (MNUM) 118,requesting issue for the user's app of an unused non-geographic number(this non-geographic number will become an identifier for the newlycreated account). Typically, MNUM 118 provides operations for numberselection and reservation, allocation, cancellation, number activationand cease. MNUM 118 allocates and provides a non-geographic number toMCSO 114 which stores the non-geographic number as part of the userprofile on customer database server 116. MCSO 114 also copies thenon-geographic number to Switch Manger 120 together with the customer'smobile number. Switch Manger 120 generates a password, which itassociates with the non-geographic number, and provides the passwordtogether with the non-geographic number and the customer's mobile numberto softswitch 122, such as the Softswitch from BT. A Softswitch isunderstood as a software controlled call server supporting multipleprotocols and which implements message conversion from one signaling andaddressing scheme to another, e.g., number translation.

Softswitch 122 sets up a SIP account for the non-geographic number (i.e.where the non-geographic number is the account ID and network number ofthe SIP account). Softswitch 122 then responds to Switch Manger 120 witha “success” message. Switch Manger 120 notifies the “success” message toMCSO 114 together with the non-geographic number and the passwordgenerated by Switch Manger 120. MCSO 114 appends an indication of thenon-geographic number to the password and copies both to the userprofile on customer database server 116. Customer database server 116now has a record of the user's VoIP account SIP credentials (i.e.non-geographic number and SIP password).

As shown in FIG. 3 a at 310, mobile device 10 contacts API Layerapplication 106 to initiate sign-up and provides the followingparameters: existing account ID (if available), home phone number (DN),mobile station international subscriber directory number (MSISDN) anddevice ID. MSISDN is used as an identifier for a mobile terminal devicein a mobile communications network.

As shown in FIG. 3 a at 312, API Layer application 106 contacts customerdatabase server 116 to lookup existing user account (if available) or torequest creation of a new account. At 314, customer database server 116responds to API Layer application 106 providing the user's existingaccount number or newly-generated account number.

At 316, API Layer application 106 send a request to billing server 126comprising the user's existing account number and home phone number (DN)to verify whether the user has a valid billing account. At 318, billingserver 126 responds to the request from API Layer application 106.

At 320, API Layer application 106 creates PIN1 code. At 322, API Layerapplication 106 contacts customer database server 116 to requestcreation of a User Profile. The request comprises the user's existingaccount number, MSISDN, device ID and the PIN1 code.

As shown in FIG. 3 a at 324, API Layer application 106 contacts mobilenetwork 112 to send PIN1 code via SMS to mobile device 100. At 326,mobile network 112 contacts mobile device 100 via SMS with PIN1 code.The user then reads the code transmitted via SMS and enters it in theapp running on mobile device 10. At 328, mobile device 10 sends the codeentered by the user to API Layer application 106. At 330, API Layerapplication 106 compares the original PIN1 code with the code receivedfrom mobile device 100. As shown at 332 and 334 respectively, when thetwo codes match, API Layer application 106 contacts customer databaseserver 116 to confirm the MSISDN and contacts mobile device 100 toconfirm the code match.

As shown in FIG. 3 b (which continues the flow chart from FIG. 3 a) at336, mobile device 10 then contacts API Layer application 106 to promptfor a further code (PIN2) for verification of the home phone number. At338, API Layer application 106 creates PIN2 code and, at 340, contactscustomer database server 116 to store PIN2 code in the user profile. At342, API Layer application 106 contacts IVR platform 108 to initiateoutput of an IVR message to communicate PIN2 code to home phone 110. At344, IVR platform 108 contacts PSTN 124 to place an outbound call tohome phone 110. At 346, PSTN 124 contacts home phone 110 to allowdelivery of voice message comprising PIN2 code from IVR platform 108. At348, the user obtains PIN2 code from home phone 110 and enters PIN2 codeon the app running on mobile device 100. At 350, the app contacts APILayer application 106 to send the code entered by the user. At 352, APILayer application 106 compares the original PIN2 code with the codereceived from mobile device 100 and, at 354, contacts mobile device 100to confirm that the codes match.

As described, above, once the app is installed on mobile phone 100, itstarts to poll API Layer application 106 for user's SIP accountcredentials. Once these are available, API Layer application 106 copiesthe SIP credentials, which comprise the non-geographic number and SIPpassword, to the app, which now has all the data required to request setup of SIP calls via a data connection, e.g. VoIP calls, to softswitch122 using the non-geographic number as mobile device 100 SIP line ID(i.e. caller or calling line identification (CLI)). In more detail, whenMCSO 114 receives user's SIP account credentials they are stored oncustomer database server 116. Each poll from the app to API Layerapplication 106 results in a call from API Layer application 106 tocustomer database server 116 requesting the credentials. Once MCSO 114has provided the credentials to customer database server 116, a pollfrom the app will result in them being copied from customer databaseserver 116 to API Layer application 106 from where they are provided tothe app. Polling by the app may occur before MCSO 114 has provided thecredentials to customer database server 116, in which case, a poll willreturn no credentials and the app therefore knows to poll again.

User is now able to make outgoing SIP calls via a data connection viasoftswitch 122 for forwarding over the PSTN 124 or elsewhere. The mobiledevice app is now able to make VoIP calls to mobile numbers, landlinenumbers, SIP accounts, etc. FIG. 2 n shows screen 290 for display onmobile device 100 representing the app in use making a voice call to amobile number (although embodiments are not so limited but may supportcalls to landline numbers, SIP accounts, etc.). As shown in FIG. 2 n, inuse, the app may provide the user with access to a list of contact namesand numbers 292, one of which may be selected to initiate a call, oralternatively a keypad 294 may be provided for entering a number toinitiate a call.

A logic flow according to an embodiment is shown at FIG. 4. At 410,mobile communications device 100 is allocated an identifier (the “mobileidentifier”), e.g. a mobile telephone number, for a mobilecommunications service provided by a mobile communications serviceprovider. At 420, mobile communications device 100 is also allocated anidentifier (the “second identifier”) for a second communicationsservice, e.g. a.

UI for a SIP/VoIP communications service provided by a secondcommunications service provider that may be different from the mobilecommunications service provider. At 430, switch manger 120 (optionally)generates a password, which it associates with the non-geographicnumber, and provides the password together with the non-geographicnumber and the customer's mobile number to softswitch 122. At 440,softswitch 122 receives from mobile device 100, a call request (SIPINVITE) comprising the second identifier. Softswitch 122 processes thecall request in the normal way but, in addition, appends the mobileidentifier to the received request. At 450 and 460, softswitch 122responds to SIP call request received from user's mobile phone bysetting-up an outgoing call request to the PSTN where the outgoing PSTNcall set up request is associated with the second identifier and mobileidentifier, e.g. the non-geographic number and the user's mobile number.According to an embodiment, the non-geographic number is carried in therequest in a “P-Asserted-ID” field. According to an embodiment, theuser's mobile number is carried in the request in a “FROM header” field.As a result, the mobile number will be available to the called user whowill be able to use the mobile number to return the call and, possibly,identify the caller.

The above embodiments are to be understood as illustrative examples ofthe invention. Further embodiments are envisaged and will be evident tothe skilled reader. It is to be understood that any feature described inrelation to any one embodiment may be used in combination with one ormore features of another of the embodiments, or any combination of theembodiments. Furthermore, equivalents and modifications not describedabove will be evident to the skilled reader and may also be employedwithout departing from the scope of the invention, which is defined inthe accompanying claims.

As will be understood by those skilled in the art, embodiments may beimplemented in computer program product software, any or all of whichmay be contained on various storage media so that the program can beloaded onto one or more computing devices (including the mobile devices,servers and switches described above) or downloaded over a computernetwork using a suitable transmission medium. The computer programproduct used to implement embodiments may be embodied on any suitablecarrier, readable by a suitable computer input device, such computerprogram product may comprise semiconductor, magnetic oroptically-readable media. Embodiments may be implemented by one or morehardware computing devices or systems having one or more processors andmemory storing one or more programs that when executed by the one ormore processors cause the computing devices to perform embodiments.

1. A method for initiating a call in a communications system; in whichthe communications system comprises: a mobile communications deviceconnected in a mobile communications network; in which the mobilecommunications device is allocated an identifier for a mobilecommunications service provided by a mobile communications serviceprovider and a second identifier for a second communications service; inwhich the method comprises: receiving, at a switch over a dataconnection from the mobile communications device, a request to initiatea call using the second communications service; in which the receivedrequest comprises the second identifier; the method further comprising:adding, at the switch, the mobile identifier to the received request andforwarding via a further communications network, the request comprisingboth the second identifier and the mobile identifier, in which themobile communications device is associated with a billing account forthe mobile communications service; in which the method furthercomprises: allocating to a billing account for a third communicationsservice, a charge relating to the call using the second communicationsservice.
 2. A method for initiating a call in a communications system;in which the communications system comprises: a mobile communicationsdevice connected in a mobile communications network; in which the mobilecommunications device is allocated an identifier for a mobilecommunications service provided by a mobile communications serviceprovider and a second identifier for a second communications service; inwhich the method comprises: receiving, at a switch over a dataconnection from the mobile communications device, a request to initiatea call using the second communications service; in which the receivedrequest comprises the second identifier; the method further comprising:adding, at the switch, the mobile identifier to the received request andforwarding via a further communications network, the request comprisingboth the second identifier and the mobile identifier.
 3. The method ofany of claims claim 1 and 2 in which the second identifier is anon-geographic number.
 4. The method of any of claims 1 to 3, furthercomprising forwarding the request via a PSTN.
 5. The method of any ofclaims 1 to 3, further comprising forwarding the request via a mobilecommunications network.
 6. The method of any of claims 1 to 5, in whichis the second communications service is a SIP service.
 7. The method ofany of claims 1 to 6, in which is the second communications service isprovided by a second communications service provider.
 8. The method ofany of claims 1 to 7 in which the call comprises a VoIP call associatedwith a SIP line ID comprising the second identifier.
 9. The method ofany of claims 1 to 8 further comprising: receiving, from the mobilecommunications device, a request to set up, with a third communicationsservice provider, a billing account for the second communicationsservice; in which the request comprises information identifying anexisting account with the third communications service provider; inwhich the method further comprises: allocating an identifier to thebilling account with the third communications service provider; andassociating the identifier allocated to the billing account with themobile communications device.
 10. The method of claim 9 in which theidentifier allocated to the billing account comprises an unallocatednon-geographic number.
 11. A switch comprising: a first communicationsinterface for communicating over a data connection with a mobilecommunications device connected in a mobile communications network; inwhich the mobile communications device is allocated an identifier for amobile communications service provided by a mobile communicationsservice provider and a second identifier for a second communicationsservice; in which the switch further comprises: a second communicationsinterface for communicating with a further communications network; aprocessor configured to control operation of the switch to: receive viathe first communications interface, a request from the mobilecommunications device to initiate a call using the second communicationsservice; in which the received request comprises the second identifier;add the mobile identifier to the received request and forward, via thesecond communications interface to the further communications network,the request comprising both the second identifier and the mobileidentifier.
 12. The switch of claim 11, in which is the secondcommunications service is provided by a second communications serviceprovider.
 13. A communications system comprising the switch of any ofclaims 11 to 12.